package cn.jiahua.test9;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.CopyOnWriteArraySet;

public class Test {

    /**
     * 测试Set线程安全 HashSet
     * 存储数据唯一
     * @param args
     */
        public static void main(String[] args) {

            //Set<String> set = Collections.synchronizedSet(new HashSet<>());
            Set<String> set = new CopyOnWriteArraySet();
            for (int i=0;i<100;i++){
                new Thread(()->{
                    set.add(UUID.randomUUID().toString().substring(0,5));
                    System.out.println(set);
                },String.valueOf(i)).start();
            }
        }



}
